In general, the present invention relates to a signal-passing technology for transferring signals between a plurality of units asynchronously operating at the same frequency in an information-processing apparatus such as equipment comprising parallel processors. More particularly, the present invention relates to a phase-adjustment control method for adjusting typically a data signal to the phase of a clock signal so as to correctly take in data conveyed in the data signal and relates to an information-processing apparatus adopting the phase-adjustment control method.
In an information-processing apparatus wherein a number of processors are mounted to operate at the same time, there is adopted a method for correctly exchanging data between the processors whereby data is exchanged simply by the clock frequency and phase, which are uniform throughout all the processors in the apparatus. As the clock frequency is increased to improve the performance, however, variations in the clock phase are no longer comparatively negligible. The variations in the clock phase are caused by, among other things, fabrication variations of LSIs employed in the processors and variations in length among wires between clock generators and the processors. Thus, with this method, the clock frequency cannot be increased to a value higher than an upper limit.